In response to IFN- and TNF-, the plumpness of the surface goblet cells and the overall morphology was reduced (p?0.001), whereas IL-4 and IL-13 enhanced these features (p?0.05, Figure 3(a-f)). mucus parameters and during clearance indicate that this pathway contributes to the increase in mucin production. IL-4 administration initiated 10?days after contamination increased mucus thickness and quality BRL-15572 and decreased colitis and pathogen contact with the epithelium. Thus, during clearance of contamination, the concomitant increase in IL-4 protects and maintains goblet cell function against the increasing levels of TNF- and IFN-. Furthermore, IL-4 affects intestinal mucus production, pathogen contact with the epithelium and colitis. IL-4 treatment may thus have therapeutic benefits for mucosal healing. (ETEC) causes diarrhea through secretion of enterotoxins, whereas enteropathogenic (EPEC) and enterohaemorrhagic (EHEC) induce attaching and effacing (A/E) lesions on intestinal epithelial cells. is usually a mouse pathogen that uses the same mechanism as EPEC and EHEC to colonize epithelial cells. During the mid-point of contamination, the host response to is usually primarily Th1/Th17 driven, whereas cytokines of Th2/anti-inflammatory type appear during clearance: interferon gamma (become up-regulated throughout contamination whereas mRNA become upregulated during clearance Splenopentin Acetate only . Colonic mucus consists of two layers: an inner, firm, nominally sterile layer and BRL-15572 an outer, loose layer, which is a niche for commensal bacteria . Bacterial penetration of the inner mucus layer and access to the epithelium are important determinants of colitis, both in murine colitis models and in ulcerative colitis . The highly glycosylated MUC2 mucin is the main component of colonic mucus and is secreted constitutively by goblet cells . Components released from microbes (e.g. lipopolysaccharide) as well as factors produced by innate and adaptive immune responses can cause mucin discharge [4,5]. IL-13 induces goblet cell proliferation during contamination , and treatment with IL-13 secreting cells results in increased Alcian blue staining of acidic mucins in tissue of mice with asthmatic airway inflammation [7,8]. In contrast, simultaneous addition of IFN- and TNF- to cultured cells render them devoid of mucus granules . Thus, a Th1 type response (common to Gram unfavorable bacteria such as and contamination in mice lacking Muc2 results in high mortality, whereas wild type (WT) mice clear the infection spontaneously , and clearance is usually delayed in mice with defective mucus exocytosis . bind to Muc2, and high numbers of bacteria are found among secreted Muc2 in infected animals, indicating that mucins may limit bacterial access to the epithelial surface or aid in transport of the pathogen from the epithelium . The current knowledge indicates that this cytokine environment, IgG and mucins are important for eliminating A/E pathogens [14,15]. Cytokines affect mucin production in allergic reactions, worm contamination and chronic contamination [16C22], however, the mucus related events that occur during natural clearance BRL-15572 of bacteria have yet to be elucidated. Here, we identified that this increased mucus thickness that occur during clearance of contamination is accompanied by increased mucin glycoprotein production and the cytokine environment decided the mucus thickness during contamination. The effects of the cytokines differentially expressed concurrently with increased mucus thickness on mucus related parameters were investigated in the presence and absence of infection. Methods Ethics statement All experimental procedures were approved by the G?teborgs Djurf?rs?ksetiska N?mnd (Ethic No. 261/09 and 57C2016) based on the regulation from Djurskyddsf?rordningen DFS 2004:4. The ETEC and EPEC strains have been deposited at the ETEC culture collection of University of Gothenburg and in the group of ?. Sj?ling. Permission to use the strain collection was granted by the Regional Ethical Board of Gothenburg, Sweden (Ethics Committee Reference 088C10). All samples were anonymized. Animals For the experiments shown in Figures 1, 2 and 6, 8C12-week aged, specific-pathogen-free, male C57BL/6 (Charles Rivers, Germany) and IFN–deficient (IFN-?/-)  mice on a C57BL/6 background, were bred in ventilated cages under pathogen-free conditions at the Laboratory for Experimental Biomedicine at Sahlgrenska Academy, Gothenburg University (Gothenburg, Sweden). For the remainder of the experiments, 8-week old male C57BL/6 mice were purchased (Charles Rivers, Germany) and housed under pathogen-free conditions at the Department of Rheumatology and Inflammation Research, University of Gothenburg (control/IL-4/Stat6 cohort 1) or in individually ventilated cages at the Laboratory for Experimental Biomedicine, Gothenburg University (control/IL-4/Stat6 cohort 2). The animals had a 12?h light/dark cycle, free access to water and food throughout the experiment and were monitored daily for the duration of the study. Open in a separate window Physique 1. Mucin production/transport in the mouse colon during clearance of contamination. (a-d) Incorporated GalNAz to mouse distal colon 3?h after intraperitoneal injection, TAMRA (red) and DAPI (blue). (a) non-infected and (b).